2011 Census Link project

The 2011 Census Link project to process and link the 2011 Census data to the Longitudinal Study (LS) database is underway. The 2011 Census records with an LS date of birth have been traced against the patient register held by the NHS. This enables information such as birth, death and cancer information to be linked to the traced LS members. The results of the 2011 tracing exercise show that 99 per cent of records were traced, this figure is comparable with previous decades and is one indicator of the high level of quality of the data the LS holds.

The traced LS data for 2011 has also been used in conjunction with LS data from the existing research database to carry out analysis to inform our understanding of under and over count in the 2011 Census.

The next stages of the link project are:

build the 2011 Census Link database

an alpha test of the quality of the data

update metadata supporting the research database

a beta test of the quality of the data

evaluation of quality and sign off

release of the data

A workshop involving LS user representatives was held in May 2011 to discuss the proposed structure and content of the 2011 Census Link database. The feedback from this event has been summarised into a recommendations paper and provides the basis for building our final research database. The recommendations paper will be published on the website in January 2013.

The objective of the alpha test is to determine that the LS 2011 Census database is fit for use by researchers. It will include the following quality checks.

initial checks on the integrity of the census and vital events data extracts

tracing rates

sampling fractions

census to census linkage rates

vital events linkage rates

Gathering the metadata to support the 2011 Census Link database has begun. There is a project underway to redevelop the existing LS data dictionary. This project will improve the search functionality of the dictionary and also enable publication on the web and in the Virtual Microdata Laboratory, where our users access the LS data.

The beta test is a chance for experienced researchers to use the LS database for research, before we launch the LS database to the wider research community. An event has been held to introduce the data available in the new research database and explain how the beta test will work. Further details on the beta test and how to submit an application are on the beta test page.